(Invited) Integrated Selection of Aptamers Against Biomolecules in Microfluidic Devices

Abstract

We describe a microfluidic approach to integrated and rapid selection of aptamers against biomolecular targets. Aptamers are oligonucleotides that recognize biological targets via specific affinity binding. Compared to other affinity molecules such as antibodies, aptamers can be synthetically developed for a broad range of targets and are attractive to biomedical applications both in vitro and in vivo. We have been employing microfluidic technology to realize physical and functional integration of aptamer selection, which is a complex iterative process involving affinity selection and amplification of target-binding oligonucleotides from a randomized library. Using electrokinetic or hydrodynamic manipulation of oligonucleotides, we have made early demonstration of microfluidic devices capable of efficiently and rapidly isolating aptamers against biomolecular targets, such as proteins and small molecules, within drastically reduced times (~10 hours) compared to conventional methods (several days). This integration and speedup of the aptamer selection process can potentially enable new applications of aptamers to basic biological sciences and clinical diagnostics and therapeutics.